Coffee has been enjoyed in a social capacity as far back as the 15th century. Today, the average Australian spends $74 on take away coffee every month . It’s hardly any wonder; when, for much of the nation, it is an essential for simply waking and functioning. Despite being packed with antioxidants, assisting with metabolism and enhancing energy, do you ever feel like coffee has the complete opposite effect? Feeling sleepy or tired after drinking a hot cup of freshly ground beans isn’t uncommon, so why does this happen?
Words Cassie Steele
How does caffeine work?
Your standard, but oh-so-delicious, flat white contains around 80mg of caffeine per serving (depending how/where your coffee is made.) Caffeine is a stimulant that boosts energy levels and increases alertness. Once absorbed into your blood stream, caffeine gets to work on boosting your serotonin and dopamine neurotransmitters, which can affect your concentration levels. It also increases the release of adrenaline into the body so that your heart beats faster, sending more oxygenated blood to your brain and muscles, as well as instructing your liver to release more sugar into the bloodstream, which is why you feel more energetic.
When it wears off, caffeine can cause you to feel drowsy as a result of interrupted adenosine receptors. Adenosine is the chemical produced by your body to regulate sleep -this is compromised through caffeine consumption. throughout the day your adenosine levels increase, and suppresses the activity of cells in the basal forebrain making you feel drowsy. Your body continues to produce the neurotransmitter even when your adenosine receptors are blocked. As your ‘buzz’ wears off, there is a build up of the chemical waiting to bind to its receptors, leading to enhanced tiredness.
Coffee?makes you dehydrated
Coffee is a diuretic, meaning it makes you need to urinate more frequently. As a result, your body may not be absorbing as much water as it requires, which can lead to dehydration. With less water in your body, your blood volume lowers, making it harder to get oxygenated blood to your brain – forcing the heart to work harder. This can be easily rectified by consuming two cups of water for every one cup’a joe!
If you like your coffee particularly sweet, you may find that the sleepiness is due to a “sugar crash”. The body takes around 45 minutes to process caffeine and that ‘buzz’ can last for 4-6 hours. Sugar, however, can have you up and straight back down in as little as 90 minutes.
TIP: Carbonated soft drinks/energy drinks can have similar side effects too. This means that you don’t necessarily have to cut out coffee if you are feeling a sleepy lull. Perhaps consider the types and quantities of beverages you are consuming daily, increase your water intake and you may come to find the benefits of a cup of coffee without the downside.